This
website will highlight only selected families of spiders likely to
be encountered by students and amateur naturalists in Singapore. For
easy reference, the families are arranged in an arbitrary order based
on easily observable features. See also notes
below.

Notes
on arrangement of the spider families:
The families are arranged in this way purely out of convenience.
Three points should be noted.

Families grouped together are not necessarily related to one
another.

The arrangement is not intended to reflect any evolutionary
scale, although spiders with two pairs of book-lungs (e.g.,
Theraphosidae) are regarded as being more primitive than most
other spiders.

The grouping is oversimplified. For instance, free-roaming spiders
grouped under "hunters" may spin a web (e.g., certain
Wolf Spiders and Nursery Web Spiders, as well as a few Jumping
Spiders). Certain spiders under the category of "orb-web
builders" do not build an orb-web, and certain spiders
outside this category (e.g., Uloboridae) do build an orb-web.
However, the categorisation holds good in most instances.